X0609 4 2026-09-14 0 0001561550 Datadog, Inc. DDOG 0001120741 OBSTLER DAVID M false C/O DATADOG, INC. 620 8TH AVENUE, 45TH FLOOR NEW YORK NY 10018 0 1 0 0 Chief Financial Officer 1 Class A Common Stock 2026-09-14 4 S 0 2656 221.2371 D 415411 D Class A Common Stock 2026-09-14 4 S 0 5424 222.1654 D 409987 D Class A Common Stock 2026-09-14 4 S 0 2452 223.1165 D 407535 D Class A Common Stock 2026-09-14 4 S 0 1801 224.3436 D 405734 D Class A Common Stock 2026-09-14 4 S 0 3940 225.1327 D 401794 D Class A Common Stock 2026-09-14 4 S 0 629 226.1915 D 401165 D Class A Common Stock 2026-09-14 4 S 0 562 227.716 D 400603 D Class A Common Stock 2026-09-14 4 S 0 1189 228.5826 D 399414 D Class A Common Stock 2026-09-14 4 S 0 9623 229.9206 D 389791 D Class A Common Stock 2026-09-14 4 S 0 5625 230.5076 D 384166 D Class A Common Stock 2026-09-14 4 S 0 2414 231.531 D 381752 D Class A Common Stock 2026-09-14 4 S 0 3057 232.7071 D 378695 D Class A Common Stock 2026-09-14 4 S 0 628 233.30 D 378067 D Shares sold pursuant to a 10b5-1 plan dated June 13, 2026. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $220.67 to $221.57. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $221.68 to $222.65. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $222.70 to $223.60. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $223.82 to $224.81. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $224.82 to $225.78. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $225.96 to $226.54. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $227.095 to $228.07. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $228.13 to $229.12. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $229.13 to $230.12. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $230.13 to $231.11. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $231.13 to $232.12. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $232.13 to $233.12. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $233.13 to $233.49. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Due to the 30 line limitation in Table I, this report is being filed across two forms. This is the first of two filings. /s/ Kerry Acocella, Attorney-in-Fact 2026-09-16